[Excessive daytime sleepiness and low CSF orexin-A/hypocretin-I levels in a patient with probable progressive supranuclear palsy].

We report a 74-year-old woman with excessive daytime sleepiness (EDS) who were diagnosed as probable progressive supranuclear palsy (PSP). Her EDS mimicked narcolepsy without cataplexy, because multiple sleep latency tests showed short latencies, human leukocyte antigen testing was positive for DR2/DQB1, and orexin A (hypocretin-I) concentration in her cerebrospinal fluid was undetectable. In PSP, neurofibrillary tangles appears in the hypothalamus, neuronal loss and gliosis are seen in a number of pontine and mesencephalic tegmental nuclei, substantia nigra, locus caeruleus.